Alarm device.



L. P. DIXON.

ALARM DEVICE.

APPUCATION FILED 1AN.20.1914.

Patent-ed May 15, 1917.

mmmmm LAURENS P. DIXON, OF NEW YORK, N. Y.

ALARM DEVICE.

Specification of Letters Patent.

.Patented May 15, 1917.

Application led January 20, 1914. Serial No. 813,235.

To all whom 'it may concern:

Be it known that l, LaUnENs P. DIXON, a citizen of the United States,l and a resident of New York, county and State of New York, have invented a certain new and uselful Improvement in Alarm Devices, of

which the following is a full, clear, and exact specification.

rllhis invention relates to a class of signaling devices, or horns adapted to be used on automobiles, or other vehicles, and elsewhere for sounding an alarm in emergency.

My invention has for its object primarily to provide an alarm device adapted to be operated by closing an electric circuit, or operated independently by manually manipulating an elastic bulbi, and which is designed to permit different types of reeds, or sound producing devices as well as various forms of sound projectors to be interchangeably used therewith if desired, whereby the volume and intensity of the alarm when sounded may be varied to meet the conditions of use so that the requirement for sounding an alarm of any preferred note and carrying power may be complied with. This is attained mainly by providing an air compression chamber in which the reed, or sound producing device is disposed so as to be operated when the air pressure therein is increased by closing the electric circuit, or by manipulating the bulb.

Other objects of the invention are to provide a revoluble air generator, or pump for supplying air under pressure to the compression chamber; toprovide a motor for rotating the pump; to provide an electric circuit adapted to be closed at intervals for driving the motor and the pump for operating the sound producing device; and to provide a simple and efficient housing for carrying the air generator and the motor, the said housing having a compartment serving as the air compression chamber.

A further object of the invention is to arrange the elastic bulb on the housing so that its interior communicates with the compression chamber to provide an elastic 4auxiliary chamber which is filled with air under pressure simultaneously with the charging of the compression chamber by the pump, and this elastic body of air serves as a regulator of the variable air waves caused by the variations of the pressure during the strokes of the pump when forcing the motive agent into the compression chamber. The pressure upon the sound producing device will thereby be equalized so as to sound a regular note therefrom instead of an irregular note as is incident to devices of this class.

A still further object of the invention is to provide au alarm device wherein a. numbei' of its parts may be of well known types so as to be purchased in complete forms if desired, and used in my present invention.

A practical embodiment of the invention is represented in the accompanying drawing forming a part of this specification in which similar characters of reference indicate corresponding parts in all the views, the said invention being more fully described hereinafter, and then pointed out in the claims at the end of the description.

In the drawing, Figure 1 is a` side elevation, partly in detail and partly in section, of one form of alarm device embodying my invention.

Fig. 2 is a view taken on the line Il-II of Fig. l, and

Fig. 3 is a view taken on the line III-III of Fig. 1.

The alarm device has a housing 10 which is preferably cylindrical in shape so as to permit the device to be made in a compact and serviceable form whereby it may be readily mounted upon a suitable support arranged on an automobile, or other vehicle, and elsewhere. One end of the cylindrical housing 10 is closed by a cap 11 having two spaced openings 12 and 13 therethrough, and in the central part of the inner surface of the cap is a recess which serves as a bearing 121. On the other end of the housing 10 is a head 15 having end walls 16 and 17 which are spaced apart to provide an air compression chamber, as 18. The wall 16 closes the second end of the housing 10, and centrally of this wall is a recessed extension providing a bearing` 19. Through the end wall 17 of 'the head is an opening 20, and secured to the exterior surface of this wall is a plate 21 provided with a boss 22 having a threaded passage 221 therethrough communicating with the compression chamber 1S. 0n the top of the head 15 is an upwardly extending second boss 23 having an interiorlythreaded opening 211 also communicating with the compression chamber. Interiorly of the housing between its cap 11 and the wall 16 of the head is a partition 25 which divides the housing into two conipartments 2G and 27, and through the partition is an opening` 28 which is in register with the recess of the bearing 19 of the wall 16 of the head. The compartment 27 is provided in the housing whereby it is eccentrically disposed coaxially with relation to the compartment 26 by circularly boring this end of the housing longitudinally so as to make the upper portion of the wall of greater thickness, as at 28 Fig. 2, than the lower part thereof. ln the narrow part of the wall of the housing is an opening, or air inlet 29 leading into the compartment 27. Lengthwise of the upper part of the thick portion 28 of the wall is an elongated recess, or sub-compartment 3() ha ving one end communicating with a n opening, or air outlet 31 in the upper part of the wall 16 of the head 15 to provide communication between the sub-compartment and the compression chamber, and communication between the compartment 27 and the sub-compartment 30 is'provided by an opening 32 formed through the part of the wall of the housing which separates these compartments. Thus air received through the inlet 29 will pass through the compartment 27, through the opening 32, through the sub-compartment 30, through the outlet 31, and into the compression chamber 18. To prevent the air returning` from the compression chamber on the interior of the head 15 of the housing and movably seated in the inlet 31 is a check valve 33 which may be of any suitable form. Disposed in the compression chamber 18 is a reed or sound producing device, as 34, which is connected to a horn, or sound projector 35. The reed and horn are threaded in the passage 22a of the boss 22 of the head so as to be detachable therefrom, and both the reed and the horn may be of any well known, or preferred types adapted to be operated by compressed air whereby interchangeable forms of these parts may be used in conjunction with the alarm device in order that the requirement for sounding an alarm of any desired note and carrying power may be complied with. 1While I show an interiorly threaded apertured boss for permitting a sound producing device and a sound projector to be removably attached to the head 15, it will be understood that any other suitable means may be employed in stead to enable various makes of sound producing devices and projectors to be applied to the head.

For the purpose of supplying air under pressure to the compression chamber 18 for operating` the sound producing device 34 to signal the alarm through the projector 35, inthe compartment 27 of the housing is arranged an air generator, or pump, or air blower, as 3G. The pump 36 may be of a well known form, as shown, having a'hub, or drum 37 held upon a shaft 38 which is journaled in the bearing 19 of the wall 16 of the head and also journaled in the opening 28 of the partition 25 of the housing. As illustrated in Fig. 2, the hub 37 is considerably smaller than the diameter of the compartment 27, and the shaft 38 is disposed midway therethrough. The shaft 38 is also disposed so as to be in the center of the housing` 10 relatively to its outer periphery, but this shaft is eccentrically disposed with relation to the periphery of the wall of 'the compartment 27. The hub of the pump is thereby eccentrically arranged in this compartment, and this hub is of a length whereby it fits snugly between the wall 16 of the head 15 and the partition 25 of the housing, but may be freely rotated therebetween. As is common with these forms of pumps, or air generators the hub 37 has a plurality of spaced radially disposed recesses in each of which is a movable blade 39 provided with a number of spiral springs 40 seated in the recesses of the hub for permitting the blades to be yieldingly guided inwardly and outwardly of the recesses, and these springs normally serve to force the blades in normal contact with the wall of the compartment 27 so that the air admitted into the compartment will be driven through the sub-compartment 30 and into the compression chamber 18 for increasing the pressure of the air therein sufficiently to operate the sound producing de vice.

The shaft 38 of the pump, or air generator extends through the compartment 26 of the housing, and the opposite end of the shaft is rotatable in the recess 14 of the cap 11 of the housing. Serving to rotate the pump 36 for supplying,l air under pressure to the chamber 18, on the shaft 38 and arranged in the compartment 26 of the housing is a motor 41. The motor 41 may be of any suitable make adapted to be electrically driven, for instance a form of motor having a commutator, as 42, in movable contact with which are brushes 43 and 44 provided on binding posts 45 and 46 held in the openings 12 and 13, respectively, of the cap 11. of the housing. The binding posts 45 and 46 extend eXteriorly of the cap 11. To the binding post 45 is connected one end of a wire 47 of an electric circuit 48 which operates the motor 41, and the other end o'f this wire is connected to one of the contacts of a switch 49 of preferably a well known push button type. The second contact of the switch 49 is connected by a wire 50 to one terminal of the usual form of battery 51, and to the other terminal of the battery is connected one end of a wire 52 leading to the binding post 46 of the cap of the housing. The electric circuit 48, the switch 49,

and the battery 50 may be arranged in the y vehicle so that the switch may be convenient to the chauffeur. To operate the sound producing` devicel for signaling an alarm the switch is manipulated in the usual man ner. The electric circuit Vwill then be closed from one terminal of the battery 51 over the wire 5U, through the su' itch ell), over the wire i? to the binding post l5, through the brush lf3 to the commutator of the motor, and from the second terminal of the battery the current will be transmitted over the wire 52, through the binding post lo, a the brush rril to the commutator el the motor. The rotation of the motor el will be imparted to the pump 3G for forcing air into the compartment 27 through its inlet El), thence through the opening 32, through the sub-compartment 30, and through the outlet 3l into the compression chamber 1S. lll/'hen the air pressure in the chamber 1S is thereby increased te a suliicient degree the Isound producing device will be operated for signaling an alarm, and when the circuit is opened for shutting-off the alarm the remaining air in the compression chamber will be prevented from returning through the outlet 31 by the checlr valve 33 cutting-off communication between the chamber 18 and the sub-compartment 30. While I have shown and described the specific construction of the pump 3G, it will be understood that I do not claim it as part of this invention as any preferred type of air generator may be employed in the device.

To enable the sound producing device to be operated independentlyv of the pump, the motor, and the electric circuit when desired, or in event of the latter parts being damaged, en the boss 23 of the head 15 of the housing is mounted an elastic bulb 53 of the usual, er any preferred form. Through the medium of the threaded opening 24 of this boss communication is provided between the compression chamber 18 and the interior 53a of the bulb so that by manually manipulating the bulb in the customary manner the air pressure in the compression chamber will be increased for operating the sound producing device to signal the alarm.

Also by arranging the -elastic bulb 53 on the housing so that its interior 53 is in communication with the compression chamber 18 an elastic auxiliary chamber is provided so as to be filled with air under pressure in unison with the charging of the compression chamber. This elastic body of air serves as a regulator of the variable air waves in the compression chamber which are produced by the strokes of the pump when forcing the motive agent into the compression chamber as well as by the resistance of the pressure upon the sound producing device. As the air pressure in the flexible regulator7 or ezpializer will always be equal to the maximum pressure delivered by the pump the intermittent lowering of the pressure betuecn the strokes of the pump will be raised through to a more uniform pressure by the feed of air from the regulator. The irregular vibrations of the air Waves in the compression chamber will thereby be equaliaed, and a regular note will be sounded from the sound produ ing device instead of an irregular note as is incident te devices of this class. Moreover, by frequently char g the elastic bulb with air in this manner it will be inflated for ready use 'instead of tending to collapse especially when the bulb has partially lost its elasticity.

In the foregoing description, I have cinbodied the preferred form of my invention, but I do not wish to be understood as limiting myself thereto, as I am aware that modifications may be made therein without departing from the principle, or sacrificing any of the advantages of this invention, therefore I reserve to myself the right to make such changes as fairly fall within the scope of the appended claims.

I-Iaving thus described my invention, I claim as new and desire to secure by Letters Patent:-

l. In an alarm device of the character described, a compression chamber with a valve controlled air inlet, means en the chamber whereby a sound producing device adapted to be operated by air pressure may be dctachably mounted on the chamber, an air compressing means connected to the chamber, adapted to be operated at intervals for supplying air through the valve controlled inlet to increase the air pressure therein for operating the sound producing device to signal an alarm, elastic means on and directly connected to the compression chamber, providing an auxiliary chamber which is filled with air under pressure in unison with the charging of the compression chamber, said elastic means being adapted to be manually manipulated to feed air into the com.

pression chamber to operate the sound producing device independently ef the operation of the air compressing means.

. 2. In an alarm device of the character described, a compression chamber having a partition wall provided with a valve controlled air inlet, means on the chamber whereby a sound producing device adapted to be operated by air pressure may be detachably mounted thereon, electrically operative air compressing means connected to the chamber, adapted to be operated at intervals for supplying air througl its inlet to increase the air pressure therein for operating the sound producing device to signal an alarm, and an elastic auxiliary chamber on the compression chamber between the partition wall and the sound producing device, said auxiliary chamber being filled with air under pressure in unison with the charging of the compression chamber, whereby a reserve supply of air pressure is maintained to equalize Variations the air pressure in the compression chamber to pio duce a uniform note of alarm when the Y sound producing device is operated.

(logies of this patent may be obtained for the compression chamber, adapted to be operated at intervals for supplying air through the inlet of the compression chamber to increase the air pressure therein -for operating the sound producing; device to signal an alarm, and an elastic bulb on the compression chamber, for the purpose specified.

This lspecilication signed and witnessed this nineteenth dayY of January A. D.1914.

LAURENS l. DXON.

Witnesses:

ROBT. B. ABBOTT, M. DERMODY.

five cents each, by addressing the Commissioner of Patents,

Washington, D.' G. 

